Travelling gantry structures and the like



Mar 1965 K. A. EDEN ETAL.

TRAVELLING GANTRY STRUCTURES AND THE LIKE 2 Sheets-Sheet 1 Filed Oct. 4. 1962 March 2, 1965 K. EDEN ETAL 3, 7

TRAVELLING GANTRY STRUCTURES AND THE LIKE Filed 001:. 4, 1962 2 Sheets-Sheet 2 Fig.3

United States Patent Oflice 3,171,363 Patented Mar. 2, 1965 3,171,363 TRAVELLING GAN TRY STRUCTURES AND THE LIKE Kenneth Albert Eden, Studley, and Kenneth John Bourne,

Birmingham, England, assignors to William E. Farrer Limited, Birmingham, England Filed Oct. 4, 1962, Ser. No. 228,324 Claims priority, application Great Britain, Oct. 5, 1961, 35 ,860/ 6 1 Claims. (Cl. 10529) This invention relates to travelling gantry structures and other similar structures such as for example overhead travelling cranes. All such structures will be hereinafter referred to for sake of convenience as travelling gantry structures.

One known form of mechanism for driving such structures utilises an electric motor which is mounted on the gantry and which is arranged to drive a pair of shafts extending across the gantry on either side of the motor, each shaft being connected at its outer end to a driving wheel which runs along a rail or guide. It is, of course, important to arrange that the gantry structure retains a predetermined alignment with respect to the associated track as it runs along said track and to this end it is common practice to provide each end of the gantry with an end carriage which includes one of the aforementioned driving wheels. Owing to the above mentioned necessity of maintaining the correct alignment of the gantry, such end carriages have to be relatively long (to give the required stability to the gantry) and are therefore comparatively expensive.

Alternatively, another form of driving mechanism employs a pair of stationary racks which each constitute or form part of one side of the track, the gantry having at each end a co-acting pinion which engages the adjacent rack, the two pinions being driven by any convenient means to drive the gantry along the track. This also is a relatively expensive construction and the object of the present invention is to provide new or improved means for driving a travelling gantry structure which means is of efiicient yet inexpenisve form.

The invention is now described with reference to the accompanying drawing wherein:

FIGURE 1 is a front elevation of one example of a gantry structure constructed in accordance with the invention and including two end carriages,

FIGURE 2 is a sectional side elevation taken on the line 2.2 of FIGURE 1 on an enlarged scale and,

FIGURE 3 is a fragmentary plan view of one end carriage.

Referring to the drawings, the travelling gantry structure shown spans one or more tanks forming part of a sewage disposed Works. It is however to be understood that a gantry structure in accordance with the invention may be used for other purposes. Furthermore the gantry structure may carry a crab or other mechanism (not shown) having a power operated hoist but such mechanism forms no part of the present invention.

The gantry structure itself may be constructed from beams or from frame-work which is made of a steel or a light alloy and each end of the structure is provided with a short end carriage 10. On the gantry is mounted an electric motor 11 which drives through a gear box 11a to a pair of driving shafts 12 which extend respectively to the ends of the gantry.

Each of said driving shafts 12 is connected through spur gearing l3 and 13a to a pair of sprockets 14 with which are engaged respectively a pair of endless driving elements each of which is in the form of a pair of roller chains 15, said chains 15 passing around a further pair of sprockets 16 which is arranged so that the chains extend in a direction parallel to the length of the track 17 along which the gantry is to run. The chains 15 are interconnected by a plurality of tie rods 18 associated with the rollers 19 of the chains. Each end carriage of the gantry structure may also be provided with two or more supporting wheels 20 which run along a rail 21 which extends along the adjacent side of the track 17.

Each side of the track is also provided with a series of stationary abutments 22 which are spaced apart along the length of the track and which each include an upwardly directed double toothed formation 22a adapted to engage the tie rods 18 of the co-acting driving chains 15. The arrangement is such that as each endless driving element 15 is driven by the electric motor 11 mounted on the gantry it will be laid along the track so that the tie rods 18 engage successively the abutments 22 arranged along the track, thereby providing a driving reaction which urges the gantry along the track. The pitch of the spaced abutments arranged along each side of the track is of course less than the length of the lower run of the driving element 15 but preferably the arrangement is such that at least two of such abutments engage with the driving element at any one time. Furthermore, guide means are preferably provided for ensuring that the driving element is maintained in engagement with any particular abutment until said driving element has moved longitudinally for a distance sufiicient to clear the abut ment. To this end there is provided a guide rail 23 which is carried by the associated end carriage 10 so that it extends along the upper side of the lower run of the chains, engaging the latter and thereby ensuring that the tie rods 18 of the chains will engage with the stationary abutments 22.

Thus a travelling gantry structure having driving means as above described will be positively driven in a manner such that correct alignment of the gantry structure relative to the track will always be maintained. Furthermore each end carriage of the gantry structure need only be of relatively short and inexpensive construction, whilst the expense involved in providing a rack along the whole length of the rack (as in some known constructions) is dispensed with.

Having thus described our invention what we claim as new and desire to secure by Letters Patent is:

1. In combination, a travelling gantry structure comprising a gantry and a pair of end carriages respectively at opposite ends of the gantry, a track, means supporting the structure on the track and constraining the structure to move in a predetermined path transverse to the gantry, and drive means comprising a pair of endless driving elements each consisting of a pair of roller chains in spaced side-by-side relationship and a plurality of tie rods interconnecting the roller chains, means supporting said endless driving elements in the end carriages respectively and comprising a pair of sprockets for each roller chain, means for imparting rotation to one sprocket of each pair, and two series of fixed abutments mounted at spaced positions along the track, the abutments of the two series being engageable successively by the tie rods of the respective endless driving elements as the structure is moved along the track.

2. The combination claimed in claim 1 wherein the fixed abutments each have a double toothed formation engageable simultaneously with a pair of tie rods of the associated endless driving element.

3. In combination, a travelling gantry structure comprising a gantry and a pair of end carriages respectively at opposite ends of the gantry, a track, means supporting the structure on the track and constraining the structure to move in a predetermined path transverse to the gantry, drive means comprising a pair of endless driving elements mounted respectively in the end carriages, means for s it simultaneously moving said driving elements relative to the end carriages, and two series of fixed abutments,

mounted at spaced positions along the track, the abut- With the respective driving elements as the structureais moved along the track and means on the end carriages engageable respectivelywiththeendless driving elements anents of the two series being engageable successively 1 to prevent movement thereof out of engagement with the abutments.

4. Incombination, a travelling gantry structurecomprising a gantry and a pair of end carriages respectively at opposite ends of the gantry, a track, means supporting of outgof engagement with the abutments.

toothed formation and the abutments' being engageable successively by the tie rods of the respective endless driving elements as the structure is moved along the track and means on the end carriages engageable respectively with the endless drivingelemer'its to 'prevent'rn ovement there- 5. Thercombination-claimed in claim 4 wherein the track includes apair of spaced parallel rails, and the end carriages each have a pair of rail engaging wheels constituting said structure supporting and constraining means.

the structure on the track and constraining the structure V 'to move in a predetermined path transverse to the gantry,

drive means comprising a pair of endless driving elements each consisting of a pair of roller chains in spaced sideby-side relationship and a plurality of tie-rods interconnecting said roller chains, means supporting said endless driving elements in the end carriages respectively and comprising a pair of sprockets for each roller chain,

meansfor'imparting rotation to one sprocket of each pair, two series of fixed abutments mounted atjspaced positions along'the tracks, each abutment having a double I References Cited in the file of-this patent UNITEDSTATES PATENTS 1,503,999 

1. IN COMBINATION, A TRAVELLING GANTRY STRUCTURE COMPRISING A GANTRY AND A PAIR OF END CARRIAGES RESPECTIVELY AT OPPOSITE ENDS OF THE GANTRY, A TRACK, MEANS SUPPORTING THE STRUCTURE ON THE TRACK AND CONSTRAINING THE STRUCTURE TO MOVE IN A PREDETERMINED PATH TRANSVERSE TO THE GANTRY, AND DRIVE MEANS COMPRISING A PAIR OF ENDLESS DRIVING ELEMENTS EACH CONSISTING OF A PAIR OF ROLLER CHAINS IN SPACED SIDE-BY-SIDE RELATIONSHIP AND A PLURALITY OF TIE RODS INTERCONNECTING THE ROLLER CHAINS, MEANS SUPPORTING SAID ENDLESS DRIVING ELEMENTS IN THE END CARRIAGES RESPCTIVELY AND COMPRISING A PAIR OF SPROCKETS FOR EACH ROLLER CHAIN, MEANS FOR IMPARTING ROTATION TO ONE SPROCKET OF EACH PAIR, AND TWO SERIES OF FIXED ABUTMENTS MOUNTED AT SPACED POSITIONS ALONG THE TRACK, THE ABUTMENTS OF THE TWO SERIES BEING ENGAGEABLE SUCCESSIVELY BY THE TIE RODS OF THE RESPECTIVELY ENDLESS DRIVING ELEMENTS AS THE STRUCTURE IS MOVED ALONG THE TRACK. 